The present invention relates to cargo-carrying vehicles and, more particularly, to devices adapted to be installed in such vehicles so as to restrain shifting cargo.
Enclosed cargo-carrying vehicles such as semi-tractor trailers, containers, trucks, vans, railway freight cars and the like are prone to damage due to shifting cargo loads during acceleration and deceleration of the vehicle. For example, trailers carried "piggy-back" by railway flatcars are subjected to various severe bumps and jolts both during train movement and car switching, either of which can lead to cargo shifting within the trailer which then impacts with the trailer enclosure. While most trailer walls are designed to withstand such impacts without appreciable damage, the vehicle doors tend to be vulnerable since they are generally of lighter construction and are secured to the trailer body at discrete points such as the hinges and the latch and thus have significantly less strength than the remainder of the trailer. Under severe cargo shifting, the doors may even be forced open and cargo possibly lost from the trailer.
In order to protect the doors and other vulnerable portions of a vehicle from shifting cargo, it has been a practice to provide a series of openings in the vehicle floor adjacent the vulnerable portion and to insert sturdy wooden posts in the openings such that they project upwardly from the floor so as to provide a barrier for shifting cargo. While this practice is generally satisfactory for the intended purpose, the posts tend to be misplaced during loading and unloading of the vehicle and require storage space when not in use. In addition, it is impossible to ascertain whether the posts are in position when the vehicle is closed. Thus inspection to determine whether the cargo restraining posts are properly installed involves opening the doors of the vehicle.